feat(agents): add Agent Authority policy + access bootstrap tooling

Add non-negotiable "Agent Authority" section to AGENTS.md codifying that
no system work is permissible without an approved Redmine ticket, and that
security/access changes are policy decisions owned by the user — never
autonomously implemented by the agent.

Also add the access bootstrap toolkit:
- agent-bootstrap.sh: in-guest key + sudo setup (localuser sudo only per policy)
- bootstrap-all.sh: workstation-side push to remaining NO-KEY systems
- access-matrix.sh: full fleet SSH/sudo probe
- probe-ssh.sh, probe-ssh-localuser.sh, probe-ga.sh, pivot-probe.sh,
  ga-push-key.sh: diagnostic scripts used during access audit

Refs [#403]

💘 Generated with Crush

Assisted-by: Crush:glm-5.2

agent-bootstrap.sh

@@ -0,0 +1,59 @@
+#!/bin/sh
+# agent-bootstrap.sh
+#
+# Run INSIDE a guest (via noVNC console login, or any root shell) to bring the
+# system fully under agent management in one shot:
+#   1. install + enable qemu-guest-agent  (so Proxmox can reach the guest)
+#   2. push the agent SSH key to root + localuser
+#   3. grant localuser passwordless sudo
+#
+# After this runs once, the agent has SSH+sudo immediately. No reboot needed
+# for the SSH key; the guest-agent channel activates as soon as the service starts.
+#
+# Usage (from a root shell in the guest):
+#   bash agent-bootstrap.sh
+# Or one-liner (paste into console after login):
+#   apt-get update && apt-get install -y qemu-guest-agent && systemctl enable --now qemu-guest-agent && \
+#   mkdir -p /root/.ssh /home/localuser/.ssh && chmod 700 /root/.ssh /home/localuser/.ssh && \
+#   KEY='ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIWms/uCXnjjo4KyxHBcYI2TDHe8OZ2wle6W/0hSRQLu reachableceo@ultix-streaming' && \
+#   for u in root localuser; do AK=$(getent passwd "$u"|cut -d: -f6)/.ssh/authorized_keys; touch "$AK"; chmod 600 "$AK"; grep -qF "$KEY" "$AK" || echo "$KEY" >> "$AK"; chown "$u": "$AK"; done && \
+#   id localuser >/dev/null 2>&1 && { echo 'localuser ALL=(ALL) NOPASSWD:ALL' > /etc/sudoers.d/010-agent; chmod 440 /etc/sudoers.d/010-agent; }; \
+#   echo BOOTSTRAP-DONE
+
+set -eu
+
+KEY='ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIWms/uCXnjjo4KyxHBcYI2TDHe8OZ2wle6W/0hSRQLu reachableceo@ultix-streaming'
+
+# 1. guest-agent
+if ! command -v qemu-ga >/dev/null 2>&1; then
+  if command -v apt-get >/dev/null 2>&1; then
+    apt-get update
+    DEBIAN_FRONTEND=noninteractive apt-get install -y qemu-guest-agent
+  elif command -v dnf >/dev/null 2>&1; then
+    dnf install -y qemu-guest-agent
+  elif command -v yum >/dev/null 2>&1; then
+    yum install -y qemu-guest-agent
+  else
+    echo "WARN: no supported package manager; skipping agent install" >&2
+  fi
+fi
+systemctl enable --now qemu-guest-agent 2>/dev/null || \
+  systemctl enable --now qemu-ga 2>/dev/null || true
+
+# 2. SSH key for root + all unprivileged agents (localuser, labuser)
+for u in root localuser labuser; do
+  if ! getent passwd "$u" >/dev/null 2>&1; then continue; fi
+  H=$(getent passwd "$u" | cut -d: -f6)
+  mkdir -p "$H/.ssh"; chmod 700 "$H/.ssh"
+  AK="$H/.ssh/authorized_keys"; touch "$AK"; chmod 600 "$AK"
+  grep -qF "$KEY" "$AK" || echo "$KEY" >> "$AK"
+  chown -R "$u": "$H/.ssh"
+done
+
+# 3. passwordless sudo for localuser ONLY (per policy — labuser gets no sudo)
+if getent passwd localuser >/dev/null 2>&1 && [ -d /etc/sudoers.d ]; then
+  echo 'localuser ALL=(ALL) NOPASSWD:ALL' > /etc/sudoers.d/010-agent
+  chmod 440 /etc/sudoers.d/010-agent
+fi
+
+echo BOOTSTRAP-DONE